Efficient photodegradation of dyes by a new 3D Cd(ii) MOF with a rare fsh topology

Abstract

Metal–organic frameworks (MOFs) can be regarded as 3D coordination polymers that adopt ordered porous structures and possess abundant active sites, which make them promising photocatalysts for the degradation of organic pollutants. In this work, a new metal–organic framework (MOF) with the formula [Cd₂(btec)(bmb)] (1) (H₄btec = benzene-1,2,4,5-tetracarboxylic acid and bmb = 1,4-bis(2-methylimidazol-1-yl)butane) has been synthesized and structurally characterized. The single crystal X-ray diffraction results suggest that the framework of 1 is constructed from the bmb pillars and 2D layers consisting of Cd²⁺ and the btec⁴⁻ ligand and exhibits a rare fsh topology. MOF 1 exhibits efficient photocatalytic performance for the photodegradation of methyl blue (MB), methyl orange (MO) and Rhodamine B (Rh B) with 77.48%, 41.84% and 69.04%, respectively in a 100 min time-span. The plausible photocatalytic mechanism has been proposed with the help of computational investigation, which suggested that the photogenerated electrons enhanced the sensitization of dyes and the separation of photogenerated carriers, and promoted the photocatalytic degradation of dyes.